Air tube for pneumatic tires



Feb. 2-., 1924a I M T. B.. MCLEROTH AIR TUBE FOR PNEUMATIC TIRES FiledJuly 6, 1922 2 Sheets-Sheet l Feb. 26 1924.

T. B. MCLEROTH AIR TUBE FOR PNEUMATIC TIRES 2 Sheets-Sheet 2 Filed July6, 1922 Patented Feb. 26,

Y into each compartment.

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TEGBAS BAKER ldllLll'YA "970013, ENGLAND.

Application fx1-ed July 6,

To all whom t may concern.'

Be it lrnown that l', THOMAS BAKER lle/ld Lnnorrr, of Eastburm TheCrescent, Hadley Wood, in the county of Middlesex, England, a Britishsubject, have invented certain new and useful improvements in orRelating to Air Tubes for Pneumatic Tires. of which the following is aspecification.

This invention relates to an air tube for a pneumatic tire, of the kindcomprising a plurality of sections or compartments so arranged that thepuncturing of one section or compartment will notV affect materially theeihcienoy of the tire as a Whole.

Air tubes of this kind and moulds for the production thereof aredescribed in the speciications accompanying my priory Letters PatentsNOS. 1,459,544 and. 1,379,929 imam' application for Letters "PatentSerial No. 558,635, and in such tubes a passagecalled the'feed passageruns around the inner periphery of the tube and communicates with eachof the sections or compartments by way of a valveless rubber feed tube,projecting The object of the present invention is to facilitate themanufacture of such air tubes.

According to the present invention a sepa rate element preferablysomewhat in the form of a collar stud (hereinafter called a stud) withor without a head is introduced through an aperture in the appropriatewall, the stud being formed with a fine substantially axial passagecommunicating with e passage or passages arranged transversely of thebase of the stud, i. e., that end thereof which will lie within the feedpassage when the tube is completed, and debouching at the peripherythereof.

rlhe stud, which may be made of vulcanite, compressed fibre, metal orlike substance, may be formed with a rounded head, a neck correspondingwith the thickness of the wall to be traversed and an enlarged base, aline passage being arranged axially through the head, neck and base,being arranged diametrically through the base so as to intersect oneanother and communicate with the axial passage whilst the upper surfaceof the base may be concenw trically fluted, ribbed or grooved orotherwise roughened and the neck of the stud may be similarly formed tofacilitate adhesion to the wall.

The studs may be inserted through apertures in the wall before or aftervulcanizeand two fine passages 192s. serial No. 573,235.

tion of the tube accordingto the method which is adopted for themanufacture of the tube. For instance when the tube is made in astraight length with or without an integral feed passage the studs maybe introduced into the moulds before vulcanization, and be employed incombination with the valveless rubber feed tubes, or the studs may beintroduced after vulcanization of the` air tube into the valvelessrubber feed tubes.

Similarly the studs may be vulcanized or introduced into a separatelymanufactured feed passage, or they may be vulcanized to vor passedthrough a strip ofl rubber employed to close the core-withdrawingapertures, when the latter are at the inner periphery of the tube, thefeed passage being formed Vby an additional strip of rubber united atits edges only with the air tube. 'lf desired grooves intersecting oneanother and communicating withV the axial passage through the stud maybe formed in the surface of the base of the stud instead ofpassages ytherethrough.v The studs may be turned, moulded, pressed or otherwiseproduced and the 1 apertures therethrough or grooves therein may beformed simultaneously or by separate operations.

The accompanying drawings illustrate various forms of the invention onan enlarged scale, Figure l being a central section of one form of studshown in position in a portion of an air tube, Figure 2 an inverted planof the stud alone, Figure 3 a view similar to Figure l, showing amodified form of stud, and Figure a an elevation of a further modifiedform of stud, a portion of an air tube being shown in section. Figures 5and 6 are y respectively a cross-section of one form of air tube asdescribed in the specification of Letters Patent No; 1,459,544: and alongitudinal section of part of one form of air tube as described in thespecification of my prior application, Serial No. 558,635, with thepresent invention incorporated therein.

The form of stud shown in Figures l and 2 has a substantiallyhenri-spherical head a, a neel; and an enlarged base c, a fine passage Zbeing arranged axially through the head a, neck and base c, and twotrans verse channels formed by line passages e, f being arrangeddiametrically through the base c so as to intersect one another andcommunicate with the passage d. The stud is shown in position in oneform of the valveless rubber feed tube g above mentioned ,theintersecting and communicating passages shovvn in Figures 1 and 2.,Whether Y the transverse channels be formed as through passages (Figs.1, 2 and 4) or as grooves v(Fig. 3) ,they Will prevent a collapse of thecommon feed passage from permitting a Y wall of said passage to closethe aperture or` duct leading from such passage through the stud to asection or compartment of the tire. Figures 1 and 3 also show how theupper surface of the base c may be grooved con- Vcentri/cally as at m tofacilitate adhesion to the surface ofthe Wall h.

Figure Llillustrates a form of the invention in which thefhead a isdispensed with and in which thev neck b is grooved at intervals alongits length as at n to facilitate adhesion to the Wall of the aperturethrough the Wall h and tube g. c

It is vto be understood that the arrangements ofthe passages e, fgrooves y','lc, m

land a are` not confined to the individual `forms of the inventionvinconnection with which they are described but lthat they may be appliedto other forms `alone or in combination, thus, for instance, the formfofthe invention illustrated by Figure 1 may have its neck b formed Withgrooves a, or further fluting, ribs Y or other roughening may besubstituted for Vthe grooves fn.

The passage d may, if desired, be enlarged for the greater part of itslength so as to leave a short length of fine passages, e. g., Where itopens at theA top of the head a.

Figs. 5 and 6 illustrate the employment of studs according to thepresent invention in air tubes as described and illustrated in the priorpatents and application mentionedV hereinbefore.

I claim A 1. For use in an air tube of the kind here- .in'before setforth for a pneumatic tire, a

stud having ahead, a neck, and a base, saidv head being formed With afine substantially axialpassage and said base being formed With achannel arranged transversely thereof debouching at the peripherythereof and communicating With the, passage in said head, substantiallyas described.

2. For use in an air tube of the kind hereinbeforev set forth for apneumatic tire, a stud having a neck and a base,.said neck being formedwith a 'tine' substantially axial passage and said base being formedwith a channel arranged transversely thereof debouching at the peripherythereof and communicatingwith the passage in said neck, substantially asdescribed. Y

3. For use in an air tube of the kind herev` Y inbefore set forth for apneumatic tire,va stud having a neckV anda base, said neck beingformedWith a substantially aXial passage and said baise being formed Withtransverse channels communicating With said passage and intersecting oneanother, said hannels debouching at the periphery of the ase. Y

THOMAS BAKER MCLEROTH. i

